(89c) Applications of Pseudo-Dynamic Heat Transfer Model in an LNG Plant

Abstract

The basis of this dynamic heat transfer model using enhanced ASTM C-680 methodology has been previously discussed and presented in 2012 AIChE Spring Conference under Topical 6: 12th Topical Conference on Gas Utilization – LNG Plant Safety and Protection. This paper outlines more of the applications in LNG plants as well as recent development made in the algorithm.

Dynamic heat transfer is critical and applied in almost every project phase for assuring adequate design and safety. In general, the applications involve heating or cooling a piping system by a flowing fluid. The parameters that need to be analyzed may include, but not limited to, fluid flow rate, fluid outlet temperature, piping metal temperature, duration to cool or heat a piping system to its design temperature, pipe length, pipe segment location of a spec break or a temperature instrumentation transmitter location, and temperature instrumentation set point.

Most applications in an LNG plant can be performed using the current dynamic heat transfer model. This paper demonstrates a hypothetical scenario where any of the parameters could be unknown and how data generated from applying the current heat transfer model could be extracted to resolve the unknown parameters. In this particular scenario, material of construction spec break is the main topic. Additional applications are also presented with the corresponding development in the algorithm. Complexity of this model can be more involved depending on the piping network, presence of fluid phase change, and heat transfer correlations used. These complexities are also discussed in this paper.